Simplify the following expression: $k = \dfrac{10p - 10m}{5m + 15n} + \dfrac{25p + 5}{5m + 15n}$ You can assume $m,n,p \neq 0$.
Answer: Since the expressions have the same denominator we simply combine the numerators: $k = \dfrac{10p - 10m + 25p + 5}{5m + 15n}$ $k = \dfrac{35p - 10m + 5}{5m + 15n}$ The numerator and denominator have a common factor of $5$, so we can simplify $k = \dfrac{7p - 2m + 1}{m + 3n}$